Liquid-level gauge



DL H. REEVES LIQUID LEVEL GAUGE Filed D60. 3, 1920 May 20, 1930.

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Patented May 2.0,` 1930 LIQUID-Lavar. GAUGE .DONALD H. REEVES, or DAYTON, omo

Application filed December e, 1920. serial 1ra-428,696.-

My invention relates to hydraulically oper- -ated gauges for visually indicating -the level or quantity of liquid in a tank or reservoir.y

The invention primarily ,is designed'f'or use lt on aircraft of all kinds and especially airplanes to indicate at the instrument board the quantity of gasoline or other liquid fuel in the main reservoir. f

It is desirable, especially in airplanes, to 104 have a liquid fuel level gauge operated otherwise than mechanically in order that the indicating dial or indicator maybe located at a point remote from the reservoir both as Vregards distance and intervening objects. A further object of my invention is to provide a liquid level gauge which entirely eliminates the use of a gland between' the reservoir-and the indicator; Another object -in Y view is to provide a hydraulically operated liquid level gauge which will correctly indicate the level or quantity of liquid fuel in the reservoir regardless of changes in the temperature. f y

Other objects and advantages of the invention will appear as the description -proceeds. i

In the accompanying drawings:

Figure 1 is a view partly. in vertical section and partly inelevation showing the mechanism of the gauge,

Figure 2 is a vertical sectional view ofthe indicator. l

Referring primarily to Figure 1 of the drawings,` 1 designates a casing of any suitable material such as sheet metal the same being securely fastened in1 a fixed position to the bottom of a tank or reservoir 1*". Attached to the top of the casing 1 is av bellows 2',

the lower end of which-is fastened to a verticallypmovable diaphragm 3. To the under the upper end of another bellows 4 and the bottom of the bellows 4 is xedly attached to the bottom of the casing 1. The bellows 2 and 4 have the same capacity and each of said 5 hereinafter described. 3

bellows is in the form of a cylinder having a Attached to the diaphragm 3 `is a bail Bussum shaped yoke 5 having fastened; to the top thereof a block or bearing member 6 which rests against a cam 7. Fastened to the cam 7 and extending therefrorbm is a rod or stem 8,

and at the free end of said rod is afloat 9.

All the mechanism here described is contained within the tank or reservoir la, the iloat 9 being adapted to .rise and fall with. the level ofliquid in said reservoir."y

' Communicating with the top of the bellows 2 is one end of a tube 10 which at its other end communicates with a bellows llthrough a block or head 12 as shown, said block having a passage 12a extending therethrough and opening into the bellows 11. j Communicating with the bellowsl 4 is another tube 13 which at its otherl end communicates with still another bellows 14 by meansof a passage 12b extending through the block or head 12 and communicating with said bellows 14. The bellows 14 has its lower end attached to the block or head 12 andn has attached to its upper end a cup 15 which `carries a centrally arranged guide rod 16 movable in a tubular guide 17 attached to the-upper gauge housing 18, the bottom of which is :fastened to the block or head 12. To the bottom of the head 12 there is attached the upper end ofthe bellows 11 and the latter has attached to itslower end a cup 19 carrying a'guide rod 2O working 'in a tubular guide 21 attached to thebttom vof they lower gauge housing', 22, the top of \11 and 14 have ther same capacity. The bel- -lows .2, tube 10 and bellowsll containa liquid having a low coeiiicientof expansion and having the same volume as the same kind ofV liquid contained in the bellows4,*tubek13a1`1d? bellows 14.

Attached to the cup 19 is an arm 23 and to the top of said arm is pivoted a' link 24. Atl the inner end of the link 24 there is another link 25 which is pivotally attached at its upper end to the cup 15. Pivotally attached to the link l24 between .the members 23 and 25 is another link 26 extending downwardly and lhavin its lower extremity n pivotally con-l necte toa sector gear 27 vwhich meshes with a pinion or gear 28- having attached thereto a pointer 29`movable over a graduated scale 30 Y cam 7 and lifting the diaphragm 3 by means of yoke 5 and block or bearing member 6. This forces the liquid contained in the bellows 2 through the tube 10 into the bellows 11,. the expansion of which forces down the cup 19. At the same time the diaphragm 3 in raising, expands the bellows 4 which draws liquid from the'bellows 14. This forces cup 15 downwardly. Since the bellows 2 and 4 are'identical and the bellows 11 and 14 are identical the motions of the cups 19 and 15 will be the same. Thus arm 23 and link 25 and therefore links 24 and 26, willvmove simultaneously, forcing downwardly the sector gear 27 which by turning gear 28 moves the pointer 29 over the graduated scale, indicating the quantity or level of liquid in the reservolr on the scale 30, the latter being calibrated for the particular reservoir.

Now assume an increase in temperature. The liquid at eachside of the diaphragm 3 will expand and through tubes 10 and 13 will expand the liquid in the bellows 11 and 14. In such case the arm 23 and lilik 25 will y move the same amount but in opposite directions and thus the link 24 will simply turn p about its central pivot and will not move the link 26. The pointer 29 will therefore remain motionless. A

While I have herein shown and described one embodiment of the present invention it is to be understood that the same principles may be carried out in other ways as defined within the scope of the appended claims.

What I claim is:

1. In a liquid level gauge, the combination of a liquid reservoir having opposed bellows positioned therein, a plate between said bellows andconnected to each ofthe same, a float in said reservoir, means for imparting movement to said plate and said bellows upon movement of said float, an indicator including opposed bellows, iuid conducting conduits connecting said flrst n'amed bellows respectively with said second named bellows and visual indicating means 4connected to and actuated by the movement of said second named bellows. 1

2. In a liquid level gauge, the combination of a liquid reservoir, opposed bellows in said reservoir, a plate, said bellows having their opposed ends secured to said plate, a loati in said reservoir, means for imparting movement to said plate upon movement of said iioat to expand one bellowsand contract the otherupon? the rise and fall of the liquid in said reservoir, pressure responsiveindicating means without said reservoir and indicator operating means in communication with and actuated by said bellows.

3. In a liquid level gauge, the combination of a liquid reservoir, opposed bellows innsaid reservoir, a plate, said bellows havin their opposed ends secured to said plate, a oat in said reservoir, means including a cam for imparting movement to said plate upon move ment of said float to expand one bellows and contractthe other upon the rise and fall vof the liquid in said reservoir, pressure responsive indicating means without said reservoir and indicator operating means in communication with and actuated by said bellows.

4. In a liquid level gauge, the combination of a liquid reservoir, opposed bellows insaid reservoir, a plate, said bellows having their opposed ends secured to said plate, a yoke connected to said plate, a cam in engagement with said yoke, a ioat in said reservoir in connection with said cam whereby said yoke is moved by the movement of said float in said reservoir, and by the connection of said yoke with said plate to expand one bellows and contact the other upon the rise and fall ofvthe liquid in said reservoir, pressure responsive indicating means without said reservoir and indicator operating means in communication with and actuated by said bellows.

In testimony whereof I have affixed my sig- 

